bsc chapter 7

what two protiens participate in facilitated diffusion

-channel proteins -carrier proteins

What is a membrane made of

-double layer of phospholipids -embedded with proteins

how do channel proteins work

-quick -water and solte

how do carrier proteins work

-slower bc it has to change shape to transport -just solute

Active and passive transport of solutes across a membrane typically differ in which of the following ways?

Active transport always involves the utilization of cellular energy, whereas passive transport does not require cellular energy.

In facilitated diffusion, what is the role of the transport protein?

Transport proteins provide a hydrophilic route for the solute to cross the membrane.

Phagocytosis occurs when

a cell engulfs a large particle

The force driving simple diffusion is ________, while the energy source for active transport is ________.

a concentration gradient; ATP hydrolysis

what is the purpose of a membrane

a selective barrier that allows sufficient passage of oxygen, nutrients, and waste

For a protein to be an integral membrane protein, it would have to be _____.

amphipathic

what molecules dramatically increases the rate of diffusion of water across cell membranes?

aquaporins

hypotonic

concentration is greater inside thing so water will move in and it will expand

hypertonic

concentration is greater outside so water will move out and thing will shrink

___________ are membrane bound organelles, while _________ are not.

eukaryotes and prokaryotes

how do unsaturated fatty acids affect the membrane

increases fluidity

Endocytosis moves materials _____ a cell via _____.

into membraneous vesicles

Which of the following membrane activities requires energy from ATP hydrolysis?

movement of Na+ ions from a lower concentration in a mammalian cell to a higher concentration in the extracellular fluid

Which of the following types of molecules are hydrophilic and therefore excluded from the hydrophobic portion of the phospholipid bilayer?

peripheral

The difference between pinocytosis and receptor-mediated endocytosis is that _____.

pinocytosis is nonselective while receptor mediated endocytosis is more selective

What is found in both prokaryotes and eukaryotes?

ribosome

what molecule can pass right through the membrane

same nonpolar molecules

isotonic

same on both sides

Osmosis

water moves across membrane from area of low concentration to high concentration

You can recognize the process of pinocytosis when _____.

when cell is engulfing extracellular fluid